Earth's Ozone Endangered By Chlorofluorocarbons

June 12, 1991|By KIRK SAVILLE Staff Writer

HAMPTON — Conditions are right for the creation of a hole in the earth's protective ozone layer above the North Pole, said a NASA Langley scientist who took part in an international Arctic research team.

``All the precursors for an ozone hole are there,'' said Lamont Poole, the assistant director of NASA Langley's Atmospheric Research Division.

Chlorofluorocarbons, widely used as refrigerants in air conditioning, refrigerators and as solvents, released into the atmosphere have caused a recurring ozone hole above Antarctica as well as a worldwide ozone depletion, scientists say.

The ozone layer, in the upper reaches of the atmosphere about 10 to 30 miles above the earth's surface, help shield the planet from the sun's ultraviolet radiation. As the ozone layer is depleted, more solar radiation hits the earth. Some scientists predict ozone depletion will result in increased skin cancer rates as well as damage to plants and aquatic life.

Poole said there was no evidence that the second hole is starting. ``The sky is not falling yet, but it could start falling,'' Poole said. ``I don't think anybody would say there's the beginning of a hole.''

He was a member of an international team of scientists who studied the Arctic atmosphere in the winter of 1989. Their findings were recently published in Science magazine.

``An Arctic ... hole, smaller and less intense than the Antarctic ... hole, is possible in the near future,'' the article concludes.

``It's a real problem,'' Poole said. ``It's not something that's imagined. It's not something that may or may not happen down the road. It's happening now.''

He said chlorofluorocarbons are distributed evenly around the globe, but weather patterns in Antarctica make the ozone problem worse in that region. During the arctic winter, cold temperatures and swirling winds contribute to form a unique weather pattern that aids in the breakdown of chlorofluorocarbons into free chlorine atoms that destroy ozone molecules.

Temperatures over the North Pole typically aren't as cold as those over the South Pole, meaning the ozone is not destroyed as fast over the Arctic area, Poole said.

The team of 200 scientists, including 18 NASA Langley researchers, used a DC-8 and a modified U-2 spy plane to collect the data over a six-week period. A similar effort is planned this winter.

International efforts are centering on limiting production of chlorofluorocarbons, and industry is seeking to develop non-destructive substitutes. But Poole said the chemicals already released will be in the atmosphere for years before causing destruction of the ozone.

``At least for the short term, there's no way to turn it around,'' he said. ``It's not a process that can be stopped overnight.''